The present invention relates to a pressure release arrangement for a container, especially for the safety containment of a pressurized water nuclear reactor in connection with which it is utilized to provide for safe pressure release before the occurrence of a containment explosion.
Pressure reduction in containers may be achieved by operational measures which, during failures, always impart certain insecurities. It is generally safer to install in the safety containment a suitable pressure relief valve which is independent of operational actions.
It is the object of the present invention to provide a release valve which remains securely closed during normal operating pressures in the safety containment and which opens only just before rupture of the containment would otherwise occur since otherwise, that is, if the valve could open earlier, containment integrity during the normal, more likely accidents for which the containment was designed might be questionable.
It is also to be taken into consideration that testing of the valve for proper operation is not possible when such a valve is installed since the valve opening pressure is above the operating pressure for which the containment is designed. Such a valve therefore needs to be composed of simple structural elements which can be exactly calculated by well established stress analysis techniques.